8.5 Translation Flashcards
What are the bases for the start codon on the mRNA molecule?
AUG
If the base sequence on a mRNA molecule is AUG,GGC,ACU,UCG. What is the tRNA molecule base sequence?
UAC,CCG,UGA,AGC.
In which organelle does translation occur in prokaryotes?
Ribosome
In which organelle does translation occur in eukaryotes?
Ribosome
What is the end product of translation?
A polypeptide chain
What are the differences between the structure of mRNA and tRNA?
tRNA: *clover shaped,
* has specific base pairings,
* hydrogen bonds between specific base pairs,
* has an anticodon,
* have an amino acid binding site
mRNA: *straight long chain,
* no base pairing,
* no hydrogen bonds,
* has codons (aka base triplets)
What carries the amino acid to the ribosomes?
tRNA
What does tRNA stand for?
Transfer Ribonucleic Acid
Which part of the tRNA molecule pairs with the mRNA codons?
The anticodon
Once two tRNA molecule have brought their amino acids to the ribosome, what happens next?
A peptide bond forms between the two amino acids causing the first tRNA to leave the ribosome and attach to another amino acid.
What determines the order in which amino acids are linked?
DNA base sequence/Order of codons on the gene/mRNA.
What is the chain of amino acids called?
A Polypeptide chain.
A mRNA molecule has 64 codons but only 63 amino acids are in the polypeptide chain, how come?
One of the codons on the mRNA molecule is a stop codon. So an amino acid is not coded for here. This causes for there to be 1 less amino acid than the number of mRNA codons.
How are identical polypeptides formed?
Many ribosomes pass immediately behind the first ribosome so the polypeptides can be assembled simultaneously.
What do genes precisely determine?
The proteins a cell manufactures.
Explain how genes control a cells activity?
Genes determine the order of amino acids in the polypeptide chain. Enzymes are a type of protein so are made from genes. Enzymes help carry out the cells activities so genes effectively control the cell’s activities.
If the anticodon on a tRNA molecule is GAU, what is the base sequence on the DNA molecule?
GAT
What are the 4 bases on a mRNA molecule?
Guanine
Cytosine
Adenine
Uracil
What are the 4 bases on a DNA molecule?
Guanine
Cytosine
Adenine
Thymine
What base is on a DNA molecule but not a mRNA and tRNA molecule?
Thymine
What is Thymine replaced with in the mRNA and tRNA molecule?
Uracil
